_indexed_ iteration using opApply or range

[spir]

Hello,

Had a nice time figuring out how to let opApply allow index iteration like:
    foreach (i, x ; collection) {}
Finally managed to do it adding 'i' everywhere:

struct S1 {
    private int[] elements = [];
    int opApply (int delegate (ref uint, ref int) block) {
        foreach (uint i, int n ; this.elements)
            block(i, n);
        return 0;
    }
}

Is this the intended idiom?
Now, I'm trying to make this work with ranges instead (input range only as of 
now). Seems i'm not smart enough to guess it alone...

Thank you,
Denis
-- -- -- -- -- -- --
vit esse estrany ☣

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